AMMAN, Jordan—The air force chief threatened more airstrikes against Islamic State in Syria, saying his country was determined to wipe out the extremist group after it killed a captive Jordanian pilot.

Jordan, a longtime partner in the U.S.-led air campaign against Islamic State, is in the midst of an intense series of airstrikes after a video surfaced last week that appeared to show Islamic State militants burning the captured pilot, First Lt. Muath al-Kasasbeh, alive in a cage.

“We have achieved our goals in revenge for Muath” after recent strikes, Gen.
Mansour al-Jbour
said at a media briefing. “But this isn’t the end,” the air force chief added.

The pilot’s killing drew condemnation from world leaders and a vow of revenge from Jordan’s
King Abdullah II.

After the video emerged on Tuesday, Jordan initially responded Wednesday by executing two convicted terrorists, one of whom Islamic State had sought to free in a prisoner swap.

In the following days, the country launched an intense series of airstrikes targeting the group’s strongholds in Syria.

The first round began on Thursday, when Jordanian fighter jets attacked 19 Islamic State targets in Syria, including headquarters and training facilities, Gen. Jbour said.

Strikes on Friday hit another 18 targets, including ammunition depots, he said. On Saturday, Jordan destroyed 19 more targets. Aircraft from the U.S. and other allies supported those strikes.

Jordan, which joined the anti-Islamic State coalition in September, has since flown 946 sorties in total, Gen. Jbour said.

The aim of the latest airstrikes was to break Islamic State’s command structure, disrupt revenue sources, destroy training centers and interfere with logistics, the general said. The attacks took place in and around the city of Raqqa in Syria, Islamic State’s de facto capital, as well as in Hasakah province in eastern Syria, according to the Jordanian military.

Future strikes against Islamic State may not continue with the same momentum as in recent days, the air force chief said.

But Jordan is nonetheless “determined to wipe [Islamic State] off the face of the earth,” he added.

The U.S. provided almost two dozen aircraft to support strikes on Thursday, according to the Pentagon, while the United Arab Emirates said Saturday that it had moved an unspecified number of F-16 fighter jets to Jordan as a gesture of support.

The Jordanian government was “coordinating at the highest level” on counterterrorism efforts with the U.A.E., according to the U.A.E.’s official WAM news agency.

The U.A.E. stopped airstrikes for the coalition out of safety concerns after Lt. Kasasbeh was captured in December, when his plane went down over Syria.

Islamic State claimed Friday that one of the Jordanian strikes killed an American woman the group was holding hostage, aid worker
Kayla Jean Mueller.

The claim couldn’t be verified, however, and Islamic State offered no concrete proof of her death.

Jordanian officials cast doubt on the claim, while authorities in the U.S. said they were investigating.